There are many uses for fastener installation guides in the construction, carpentry and power tool fields. In certain circumstances, it is preferable for fasteners, such as screws, to be installed at a horizontal or vertical orientation relative to the work surface. In other instances, a worker may need to install the fastener at a prescribed angle relative to the work surface. For example, building codes require the structural connection between wooden components, such as a top plate and a roof truss, to meet certain structural strength requirements. To have sufficient structural strength between framing components, toe-nailed connections with nails and spikes are installed at an angle near 30° to the vertical. Similarly, threaded fasteners, such as screws, are driven through the top plate and into the roof truss at an angle near 22.5±5° to the vertical, the optimum angle which maximizes the strength of the connection between the top plate and the roof truss.
Previous guides such as protractors, squares or other similar type devices are clumsy and require the operator to perform the difficult task of holding the guide and installing the fastener at the same time. Other guides, such as a bubble level, have been built into power tools but the majority of tools in use by operators don't include this feature. Moreover, some guides attach to the power tool, but these tools are bulky, clumsy, located remotely from the bit and take time to be attached and removed from the power tool.